1. Field of the Invention
This invention relates to bird feeders and, more specifically, to a bird feeder which closes the food ports when the perch is tilted by the presence of a pest on the perch thereby simultaneously ejecting the pest from the perch and closing the food ports.
2. Prior Art
A well-recognized problem with bird feeders is their attraction to a wide variety of pests who will go to extreme lengths to eat the bird food intended for small song birds. Squirrels are one of the most persistent of these pests and have an annoying ability to find a way around the barriers placed in their way. The term “pest” or “pests” as used herein refers to a wide variety of creatures including but not limited to squirrels, racoons, rats and large birds, such as hawks.
Various patents have been issued on bird feeders which are intended to prevent the consumption of the bird food by pests. One approach used is to provide a platform or perch which will tilt so as to force the pest to fall to the ground. Another approach is to cause the food supply to be cut off by closing the food ports from which a pest can obtain the bird food. However, the prior art does not teach a bird feeder which both forces the pest from the perch and also closes off all access to the bird food.
Many of the proposed bird feeders are complex and it is commonplace but not universal in the designs to utilize springs. As is well known, springs weaken resulting in a lessening of the period of use before maintenance is needed.
One attempt to protect a bird feeder is found in the Latham Patent, U.S. Pat. No. 4,523,546. This patent teaches a flexible sheet, either at the top or above a bird feeder. The flexible sheet will fold down when a pest attempts to become positioned on it and the pest accordingly will slide off the sheet. This device offers some protection but cannot serve any benefit as to pests that fly.
The Czipi Patent, U.S. Pat. No. 5,964,183, has a vertical cylindrical storage facility with aces ports to the bird food at the lower end. An outer shroud is forced downwardly by the weight of a pest to close the food ports. The weight of a pest overcomes either a spring-loaded lever or a weight. Access to the bird food is denied but the pest is not forced off the perch.
The Banyas et al Patent, U.S. Pat. No. 6,415,737, teaches spring-loaded perches which fold down and which force the pest off the bird feeder but which do not close off the food ports.
The Cote Patent, U.S. Pat. No. 8,543,384, teaches a hanging bird feeder with an elongated storage container, which is located vertically and is covered at the top from which the bird feeder may be suspended. At the base, a perch is isolated with food ports adjacent the food ports. Although the perch is moved slightly lower, the pest is not expelled from the bird feeder.
The Hardison Patent, U.S. Pat. No. 6,591,781 also teaches a feeder, which like the Cote Patent, provides for a perch which moves when occupied by a pest. The perch does move and may even tilt but not sufficiently to force the pest off the perch. The Hardison Patent essentially teaches a bird feeder which closes the food ports to the bird feeder due to the weight of the pest. An ejection of the pest does not occur.
The Faschio Patent, U.S. Pat. No. 6,622,654, teaches a perch which folds down significantly when a pest occupies the perch. Most pests are accordingly forced off the perch but access to the bird food remains open for any pest who can retain a position by the bird food.
A bird feeder, which was not the subject of any known patent, also provides for forcing the pest off the perch but leases open access to the bird food. That design has a cylindrical member extending from the storage container which is closed off by a barrier. A disc-shaped perch is located at the lower end of the cylindrical member and is held in place by a spring expending from the center point of the perch to the center point of the barrier. The perch has a diameter significantly larger than the dimmer of the cylindrical member. The strength of the spring is inadequate to support a pest on the perch and will tip down dislodging the pest but will remain in place on the bottom of the cylindrical member when the perch is occupied by the desired song birds. Notwithstanding the assumed ejection of the pest, the food ports located in the cylindrical member above the barrier remain open. Should a pest be able to hang onto the perch or to fly, the bird food could still be consumed by the unwanted pest.